1. Field of the Invention
The present invention relates to a board-to-board electrical connector and a method for effectively make such connector, especially a method whereby parts of the connector can be installed quickly without causing damage.
2. Description of the Related Art
As detailed in pages 1737-1755 of Proceedings of 1990 National Electronic Packaging and Production Conference (NEPCON WESTxe2x80x290) (V01.2), board to board electrical connectors have been widely used and applied in all kinds of electrical equipment to electrically connect two separate Printed Circuit Boards (PCBs). A conventional board-to-board connector comprises an insulative housing defining a plurality of channels, and a plurality of conductive contacts respectively received in the channels. Each contact comprises a medial portion, an arcuate resilient contact portion extending from the medial portion, and a terminal portion. The terminal portion extends substantially perpendicularly from the medial portion, and is used for soldering to a respective pad on a lower PCB by Surface Mounting Technology (SMT) soldering.
The conventional process for placing the contacts in the housing is to push the contacts into the channels to a certain extent with a common carrier that interconnects either the contact portions or the terminal portions of the contacts. If the carrier connects with the terminal portions, the contacts must be installed into the channels from the bottom face of the housing.
However, during the process of installing the contacts into the housing, the housing applies force on the contacts in a direction opposite to the direction of installation. This renders the housing liable to disengage from the contacts. In particular, when a mating complementary connector is detached from the board-to-board connector in normal use, the housing is prone to separate from the contacts. In addition, excessive or uneven pushing force may be exerted on the contacts during the installation process. The contacts may be improperly positioned in the channels, and the contact portions may be distorted. As a result, reliable electrical engagement between the contacts and conductors of the complementary connector may be impaired. Furthermore, the contacts are usually gold-plated for better electrical performance. If the contacts or the connector have to be discarded, this is costly.
Hence, a new board-to-board connector manufactured by an improved method is required to overcome the above-described disadvantages.
An object of the present invention is to provide an electrical connector which enables safe installation of its contacts in its housing, thereby facilitating reliability of the contacts and effective electrical engagement of the connector with a complementary connector.
Another object of the present invention is to provide a method for manufacturing an electrical connector which enables safe installation of its contacts in its housing, thereby reducing defect run rates in mass production facilities.
A further object of the present invention is to provide an electrical connector having contacts reliably secured in a housing thereof.
In order to achieve the aforementioned objects, an electrical connector in accordance with a preferred embodiment of the present invention comprises an insulative housing receiving a plurality of conductive contacts. The housing comprises a central island portion surrounded by connected sidewalls. The island portion is separated from the sidewalls by a moat-like mating groove. A plurality of closely-spaced receiving slots is defined in each of opposite longitudinal sides of the island portion. Each slot comprises a first channel and a second channel. If a transverse cross-section of the housing is viewed, the first channel is wider than the second channel. Each contact comprises a contact portion, a terminal portion, and a medial portion which connects the contact portion with the terminal portion. The contact portion is flexible, and adapted to engage a mating contact of a complementary connector. The terminal portion extends approximately perpendicularly from the medial portion, and protrudes out of the bottom face of the housing for soldering to a printed circuit board.
In manufacturing the electrical connector, two series of contacts are made, one series for each longitudinal side of the island portion of the housing. Each series of contacts is stamped from a sheet of conductive metallic material. The series of contacts is connected with a common operation carrier. The terminal portion of each contact extends at a slight angle from the medial portion, and an L-shaped pull portion is formed at a distal end of the terminal portion. The series of contacts are inserted into its corresponding slots of the housing by applying force on the operation carrier. The pull portions are pulled away from the housing in a direction parallel to the slots until the terminal portions are completely exposed outside of the housing.
Other objects, advantages and novel features of the present invention will become more apparent from the following detailed description when taken in conjunction with the accompanying drawings. A copending application Ser. No. 10/243,427 with the same assignee, discloses a somewhat close approach.